The ethanol production at elevated temperature, 40 °
C, was preliminary tested
in YPD medium, pH 5.5. In shake flask experiment, to observe the effect of nitrogen
source, carbon source and pH for ethanol production, M9 minimal medium was used.
The thermotolerant yeast strain S1 was able to produced ethanol up to 74.58%
theoretical from 5% (v/v) glucose in M9 minimal medium pH 4.0 when ammonium
sulfate as a nitrogen source. The optimum condition for ethanol production in shake
flask experiment was observed in 2 liters fermenter. The yeast gave the highest cell
dry weight and produced ethanol within 24 hours. After end of aerobic fermentation